Diabetes patients need to measure the blood sugar level regularly and administer insulin based on the blood sugar level to maintain a normal blood sugar level. To maintain this normal blood sugar level, diabetes patients need to measure the blood sugar level regularly, sample a small amount of blood from fingertips using a blood test apparatus, and measure the blood sugar level from this sampled blood.
The conventional blood test apparatus generally uses a needle as a means for puncturing skin (see Patent Document 1, for example). As shown in FIG. 1, conventional blood test apparatus 1 which uses a needle as a puncturing means, includes: housing 2 that forms a chassis; cylinder body 3 that is provided at which one side of housing 2 opens; plunger 4 that moves back and forth inside cylinder body 3; handle 5 to which one end of plunger 4 is connected; latch part 6 that latches handle 5 on housing 2; spring 7 that urges handle 5 toward opening part 3a of cylinder body 3; lancet 9 which has one end held by plunger 4 and the other end attached with blood collection needle (hereinafter “needle”) 8; holding part 11 that holds blood sensor 10 on the side of opening part 3a; and electrical circuit section 12 to which the output of sensor 10 is connected. Further, a blood test apparatus with blood sensor 10 made of replaceable member is also provided.
Blood test apparatus 1 is abutted on the skin of the patient, and latching of latching part 6 is released. Then, handle 5, urged by spring 7, is propelled in the direction of arrow 14. By this release of latching of handle 5, needle 8, connected to the handle 5 via plunger 4 and lancet 9, is also propelled at the same time. Needle 8 breaks through blood sensor 10 and punctures skin 13.
A small amount of blood flows out from punctured skin 13. The outflowing blood is guided inside blood sensor 10. The blood guided into blood sensor 10 causes chemical changes in blood sensor 10 according to the blood sugar level of the patient. The current produced by the chemical changes is led to electrical circuit section 12, and the blood sugar level is measured. The calculated blood sugar level is displayed on display section 15. Based on the calculated blood sugar level, for example, basic data showing the amount of insulin to administer to the patient is provided.
On the other hand, an apparatus for sampling blood using laser light for the puncturing means, is also proposed (see Patent Documents 2 and 3). Use of laser light provides an advantage of making unnecessary replacement of the needle and possibly alleviating the pain of the patient upon puncturing.    Patent Document 1: Japanese Patent Application Publication No. 2003-524496    Patent Document 2: Japanese Patent Application Publication No. 2004-533866    Patent Document 3: Japanese Patent Application Laid-Open No. 2004-195245